Among various electronic apparatuses including imaging apparatuses such as a still camera and a camcorder, there are electronic apparatuses that can be operated by the power of a battery. A battery is charged, for example, by being mounted in a charger and is mounted in a battery mounting unit of an electronic apparatus in a charged state. Such a charger or an electronic apparatus functions as a connection apparatus so as to be connected to the battery.
In the battery described as above, a connector including connection terminals is arranged, and electrode terminals of a charger or electrode terminals arranged in a battery mounting unit are connected to the connection terminals, and charging of the battery or the supply of power from the battery to an electronic apparatus is performed (for example, see PTL 1).
The battery described in PTL 1 includes a casing having a substantially rectangular parallelepiped shape, cells housed inside the casing, and a connector electrically connected to cells, and an identification groove (a discrimination concave part) is formed on a lower end portion of the casing as a functional groove having a predetermined function.
The battery is slid and mounted in a connection apparatus such as a charger, so that the connector and the electrode terminal are connected. When the battery is mounted in the connection apparatus, an identification protruding portion formed in the connection apparatus can be inserted into the identification groove, and a type of battery is identified on the basis of a state in which the identification protruding portion is inserted into the identification groove.